This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The utilization of pluripotent cells to form specific cell types requires an understanding of basic metabolism and the factors that affect differentiation. In this study, stem cells are being grown with 13C [unreadable]isotopically labeled substrates such as glucose, and the products of the metabolism are identified by NMR. Cells at different stages of growth and under different conditions are being examined.